Field of Invention
This invention relates to an earphone device and, in particular, to an earphone device having a resonant chamber with an adjustable volume.
Related Art
In general, an earphone device includes an open type and a closed type, both of which have their respective fans. Besides, these two types can bring different hearing experiences for users. The open-type earphone device is better at middle-high frequency performance and can bring more exquisite performance of audio frequency output especially in listening to classical symphonic music. On the other hand, in comparison with the open-type earphone device, the closed-type earphone device is better at low frequency performance and can obviously perform well especially in listening to the more powerful audio content such as drumbeat, strong-rhythm dance music, gun shot, explosion sound or special effect sound.
Therefore, regardless of the performance on audio frequency or the musical type, an obvious difference exists between the open-type earphone and the closed-type earphone. Besides, when a user likes to listen to various musical types, such as symphonic music and strong-rhythm dance music, the user needs to buy these two types of earphone devices since one of the two types can not possess the advantage of the other type. Moreover, one of these two types of the earphone devices is only for the particular type of music, so that the user can not have better hearing experience.